High resolution tape directory (HRTD) stored at end of data in an index partition

Abstract

In one embodiment, a method includes writing a file into a data partition of a tape medium, writing a pointer of the written file in an index partition and creating a high resolution tape directory (HRTD) including detailed location information of data in a data partition. The method also includes storing the HRTD as part of end of data (EOD) of the index partition in response to a tape cartridge housing the tape medium being unloaded. The storing the HRTD as part of the EOD of the index partition includes requesting movement of the tape medium to the index partition in order to update an index file after changes have occurred to data in the data partition, writing an updated index file into the index partition concurrent to writing an updated HRTD into the EOD of the index partition, and requesting for the tape cartridge to be unloaded.

What is claimed is: 
     
       1. A tape drive system, comprising:
 a file system configured to enable sequential access to data on a tape medium, the file system being enabled in at least one hardware processor; 
 a file access controller configured to manage the data, the file access controller comprising the at least one hardware processor and logic integrated with and/or executable by the at least one hardware processor, the logic being configured to cause the at least one hardware processor to:
 write a file into a data partition of a tape medium, wherein the tape medium comprises two or more partitions including the data partition and an index partition; 
 write a pointer of the written file in the index partition of the tape medium, wherein the pointer is managed by the file access controller; 
 create a high resolution tape directory (HRTD), the HRTD including detailed location information of data in the data partition of the tape medium; and 
 store the HRTD as part of end of data (EOD) of the index partition in response to a tape cartridge housing the tape medium being unloaded, the logic configured to cause the at least one hardware processor to store the HRTD as part of EOD further causing the at least one hardware processor to:
 request movement of the tape medium to the index partition in order to update an index file after changes have occurred to data in the data partition; 
 write an updated index file into the index partition; 
 write an updated HRTD into the EOD of the index partition concurrent to writing the updated index file; and 
 request for the tape cartridge to be unloaded. 
 
 
 
     
     
       2. The tape drive system as recited in  claim 1 , wherein the tape drive system adheres to linear tape open (LTO) format standards, and wherein the file system adheres to linear tape file system (LTFS). 
     
     
       3. The tape drive system as recited in  claim 1 , wherein the logic further causes the at least one hardware processor to:
 receive, via the file system, a request to read out a specified file; 
 load a tape cartridge housing a tape medium which includes the specified file stored thereon; 
 read out a pointer in the index partition to acquire directory information corresponding to a location of the specified file; and 
 read out the EOD in the index partition in order to acquire the HRTD concurrent to reading out the pointer from the index partition. 
 
     
     
       4. The tape drive system as recited in  claim 3 , wherein the logic further causes the at least one hardware processor to:
 determine whether a stored HRTD is valid; 
 validate the stored HRTD and request access to the specified file according to the detailed location information of the stored HRTD corresponding to the specified file in response to a determination that the stored HRTD is valid; 
 access location information of the specified file using a standard tape directory (STD) stored in cartridge memory (CM) in response to a determination that the stored HRTD is invalid; and 
 access the specified file at a higher speed when using the stored HRTD or at a lower speed when using the STD. 
 
     
     
       5. The tape drive system as recited in  claim 1 , wherein the logic further causes the at least one hardware processor to:
 make changes to data stored in a first portion of the data partition; 
 store detailed location data for the changed data to an EOD of the first portion of the data partition; and 
 reflect the detailed location data for the changed data in the HRTD stored to the EOD of the index partition in response to the tape cartridge housing the tape medium being unloaded. 
 
     
     
       6. The tape drive system as recited in  claim 1 , wherein the logic further causes the at least one hardware processor to partition the tape medium into the two or more partitions. 
     
     
       7. A computer-implemented method for managing detailed location information, the method comprising:
 writing a file into a data partition of a tape medium, wherein the tape medium comprises two or more partitions including the data partition and an index partition; 
 writing a pointer of the written file in the index partition of the tape medium; 
 creating, by a hardware processor, a high resolution tape directory (HRTD), the HRTD including detailed location information of data in the data partition of the tape medium; 
 storing, by the hardware processor, the HRTD as part of end of data (EOD) of the index partition in response to a tape cartridge housing the tape medium being unloaded, wherein the storing the HRTD as part of the EOD of the index partition comprises:
 requesting movement of the tape medium to the index partition in order to update an index file after changes have occurred to data in the data partition; 
 writing an updated index file into the index partition; 
 writing an updated HRTD into the EOD of the index partition concurrent to writing the updated index file; and 
 requesting for the tape cartridge to be unloaded. 
 
 
     
     
       8. The method as recited in  claim 7 , wherein the tape medium adheres to linear tape open (LTO) format standards, and wherein a linear tape file system (LTFS) enables partitioning of the tape medium. 
     
     
       9. The method as recited in  claim 7 , further comprising:
 receiving a request to read out a specified file; 
 loading a tape cartridge housing a tape medium which includes the specified file stored thereon; 
 reading out a pointer in the index partition to acquire directory information corresponding to a location of the specified file; and 
 reading out the EOD in the index partition in order to acquire the HRTD concurrent to reading out the pointer from the index partition. 
 
     
     
       10. The method as recited in  claim 9 , further comprising:
 determining whether a stored HRTD is valid; 
 validating the stored HRTD and requesting access to the specified file according to the detailed location information of the stored HRTD corresponding to the specified file in response to a determination that the stored HRTD is valid; 
 using standard tape directory (STD) stored in cartridge memory (CM) to access location information of the specified file in response to a determination that the stored HRTD is invalid; and 
 accessing the specified file at a higher speed when using the stored HRTD or at a lower speed when using the STD. 
 
     
     
       11. The method as recited in  claim 9 , further comprising:
 making changes to data stored in a first portion of the data partition; 
 storing detailed location data for the changed data to an EOD of the first portion of the data partition; and 
 reflecting the detailed location data for the changed data in the HRTD stored to the EOD of the index partition in response to the tape cartridge housing the tape medium being unloaded. 
 
     
     
       12. The method as recited in  claim 7 , further comprising partitioning the tape medium into the two or more partitions. 
     
     
       13. A computer program product for managing detailed location information, the computer program product comprising a non-transitory computer readable storage medium having computer readable program code embodied therewith, the computer readable program code being executable by at least one hardware processor to cause the at least one hardware processor to:
 write a file into a data partition of a tape medium, wherein the tape medium comprises two or more partitions including the data partition and an index partition; 
 write a pointer of the written file in the index partition of the tape medium; 
 create a high resolution tape directory (HRTD), the HRTD including detailed location information of data in the data partition of the tape medium; and 
 store the HRTD as part of end of data (EOD) of the index partition in response to a tape cartridge housing the tape medium being unloaded, wherein the computer readable program code executable by the at least one hardware processor to store the HRTD as part of the EOD further causes the at least one hardware processor to:
 request movement of the tape medium to the index partition in order to update an index file after changes have occurred to data in the data partition; 
 write an updated index file into the index partition; 
 write an updated HRTD into the EOD of the index partition concurrent to writing the updated index file; and 
 request for the tape cartridge to be unloaded. 
 
 
     
     
       14. The computer program product as recited in  claim 13 , wherein the tape medium adheres to linear tape open (LTO) format standards, and wherein a linear tape file system (LTFS) enables partitioning of the tape medium. 
     
     
       15. The computer program product as recited in  claim 13 , wherein the computer readable program code further causes the at least one hardware processor to:
 receive a request to read out a specified file; 
 load a tape cartridge housing a tape medium which includes the specified file stored thereon; 
 read out a pointer in the index partition to acquire directory information corresponding to a location of the specified file; and 
 read out the EOD in the index partition in order to acquire the HRTD concurrent to reading out the pointer from the index partition. 
 
     
     
       16. The computer program product as recited in  claim 15 , wherein the computer readable program code further causes the at least one hardware processor to:
 determine whether a stored HRTD is valid; 
 validate the stored HRTD and request access to the specified file according to the detailed location information of the stored HRTD corresponding to the specified file in response to a determination that the stored HRTD is valid; 
 access location information of the specified file using a standard tape directory (STD) stored in cartridge memory (CM) in response to a determination that the stored HRTD is invalid; and 
 access the specified file at a higher speed when using the stored HRTD or at a lower speed when using the STD. 
 
     
     
       17. The computer program product as recited in  claim 13 , wherein the computer readable program code further causes the at least one hardware processor to:
 make changes to data stored in a first portion of the data partition; 
 store detailed location data for the changed data to an EOD of the first portion of the data partition; and 
 reflect the detailed location data for the changed data in the HRTD stored to the EOD of the index partition in response to the tape cartridge housing the tape medium being unloaded. 
 
     
     
       18. The computer program product as recited in  claim 13 , wherein the computer readable program code further causes the at least one hardware processor to partition the tape medium into the two or more partitions.